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How important is crown on a soundboard?. I have read Larry's book and he mentions that crown may be found lacking in even a high quality piano. I would appreciate feedback on this topic. I have been hearing stories of rebuilds without crown. Is it acceptable for me to check the crown on a piano I am interested in purchasing?.

Many thanks,
Steve Ries

I hear with all the bad publicity surrounding Prince Charles and Di there is talk about abolishing the crown completely.

I'm not sure how the lack of crown will affect England.

Only time will tell.

I'm with Larry. I wouldn't worry about crown as long as the tone is good. However it is quite valid I think to check that you have reasonable down bearing on an old or rebuilt piano.

Regards,

Rick Clark

Rick,

How would I do that?. Is this somehting I need a tech for?.

Thanks,
Steve

I agree with Rick, Steve.

There are guages made to measure crown, but a tech. will know how to use it.

Any particular piano you are considering?

Normally you would need a tech. But if you think you're going to be checking a lot of them it might be more economical to invest in a gauge and educate yourself such as with the Reblitz book.

Regards,

Rick Clark

Rick,

Many thanks for your kind help. I tracked down the Reblitz book and it looks like money well spent.

_____

Rich,

Nothing yet but I am getting tired of fighting my old spinet. Did you get your first new AA yet?.

Thanks to both of you,
Steve

Steve,

No - but we are completing a rebuilt AA that is worth looking into. (You could also play the completed S&S D)

Briefly:
Soundboard crown is directly related to soundboard system stiffness. In general, more soundboard crown — along with the related string bearing against the bridges — will result in a stiffer soundboard system. Soundboard system stiffness is one of the two primary physical characteristics that controls sustain time. The other is the mass of the system. There are a lot of other design factors involved, but stiffness and mass are the two biggies. Incidentally, soundboard stiffness is not consistent across the compass of the piano. Nor is crown. Generally you will find less crown in the treble section but system stiffness is still important. In a typical older piano the bass and tenor may sound quite good while the region around the fifth and sixth octaves may drop dead. Or, though less common, the opposite may be true.

If you are looking at a piano that does not seem to have as much sustain as you think it should have and the soundboard has little or no discernable crown you may want to consider another piano. If you’re looking at a piano that sounds great across its full compass but has little or no crown — well, it’s a crapshoot. And it is probably time to call in an experienced technician, preferably one with some solid knowledge of rebuilding, including soundboard function. You might be looking at a piano that can still give years of acceptable service or you may be looking a an expensive problem just waiting to drain your bank account.

If you are getting ready to rebuild a piano in which the soundboard has little or no crown, it’s time to replace the soundboard.

Del

Suppose a quality rebuilder consistently produces rebuilds with little or no crown. Is this axiomatically bad, or can excellence in other areas make up for this?

Steve,

I carried a string and almost never brought along the bearing gauge when I was shopping used. If you are diciplined about placing it underneath each piano you sample, no matter how bad it may be, you will quickly observe the kind of dead/dying tone that frequently comes from crownless boards. I found dental floss worked pretty well.

I suppose I didn't try the bearing test as much because its safe to assume most all pianos are built with crown. If they haven't got it, then by design their bearing is gone/going, too. I also think there are more than a few rebuilds you are apt to come accross where the rebuilder tried to salvage a flat/flattening board by using taller bridge caps. While this may restore bearing, which can be shown using a gauge, it doesn't change the reality that the board should have been replaced.

Chris

Thanks Del,

I was hoping you would add your feedback to this thread.

Is it hard for rebuilders to build a soundboard with crown?. Or more importantly; is it hard for rebuilding shops to put together a soundboard system with suffficient stiffness?.

I would consider myself a late beginner and I want to buy a good solid piano that is going to give me many years of services but I do not yet possess the skill to be able to judge all of the important traits of a piano. Yes, I am familiar with sustain. Can you suggest certain notes or chords I can play to be able to judge the sustaining qualities of a piano?. What length of sustain do you think is sufficent?. Any input you can give is appreciated. At this point in time I am considering quility rebuilds but I am not sure I would not be better off with a lesser tier new piano. It is my understanding that even some of the best rebuilding shops are facing soundbaord issues. Maybe this is only rumor but it has me a little scared.

Many thanks,
Steve

Del
How does crown affect brightness/warmth of the tone? You talked about(and I managed to understand and stay with you) how it affects sustain, but I was curious about actual tone? Is there something about the soundboards of Asian pianos that differs from European or CW's that makes them sound brighter. Hope this isn't too dumb a question?

Chris W1,

Many thanks for the valuable input. I am really getting a lot out of this thread.

Steve

Del gave excellent insight to this question.

To me it's the old "hops" and "malt" question also regarding beer.

It's not just "what" but very much "how" - "where" and especially to "which degree" and "which "proportion"

Basically it's the type of discussion of "how the rocket flies" but the most important thing is that is *flies* at all.

Always let your own taste buds give you the first hint.

Do you think we in this business have ever played any pianos with "lots of good crown" that didn't appeal to us?

Lots.

norbert

The complaint I most often hear about formerly great old pianos is that they sound wonderful in the bass and tenor and if only they were louder and more sustaining in the top two octaves they would be perfect.

Just figure out what kind of sound you want from the top end of the scale and don't settle for anything less. If it sounds wrong it could be the soundboard or the strike points or something else, but if it was something fixable it probably would have been fixed before you were allowed to play it.

It is exacting work and needs to be done right but there are any number of good shops, both large and small, that do an excellent job of soundboard installation.

There are no benchmark tests that I can give you other than to encourage you to get lots of experience in listening. Don't just bang something out but listen critically to what you are playing. When you find a piano you like, stop and listen — try to discern why you like it. The same thing goes for a piano you don’t like — try to figure out why you don’t like it. As I said, most sustain problems show up first in the upper third of the piano’s compass.

Del

Thanks Del and everyone else for the most valuable input. I just have to take a few short pieces I know well and use them for my tests.

Finding a piano I like is a certainly a challenge but with the help of the many friends I am making here on PW the search is great fun.

Sincerely,
Steve

Del,

Just as an object lesson, I serviced a piano with sustain problems like this just today. A 1920's model that had been "restored" but nothing really major done other than restringing and refinishing.

By plucking the strings in the treble it was clear that the lack of sustain was built-in, it was not a hammer issue.

Del you have written on these issues before and I take your writings seriously. At the same time it is thought there can be other explanations for sustain problems such as a plate that is not tightly screwed down or possibly problems with the Capo bar surfaces. It was clear from the poor quality of the restringing that whoever did the work was not knowledgable or detail oriented (this piano was a M&H restored in NYC, BTW) so I had to be open to several potential causes.

However after examining things as best I could given the limits of the service call, I think the best explanation is the soundboard as you describe, with the classic "low impedance" sound in the treble.

I don't know if strictly speaking this is 'merely' crown loss, because some reading I have done on this issue points to wood ageing changes at the cellular level, which is a slightly different thing than simply loss of crown with otherwise "young" wood. I really don't know what proportion of blame goes to which specific cause, but it's an interesting subject to be sure, and one worthwhile to continue learning about.

A related subject is the restoration of the Capo bearing surfaces, which is in this same treble region of lost sustain. Though it is generally accepted that when restringing one needs to dress and shape the bearing surface, I remember reading an article long ago (in a Journal subsequently lost in Hurricane Andrew) that it may also be considered wise for the restringer to heat-temper the bearing surface. I believe the writer stated that in the old factories, heat tempering the Capo was normal practice, therefore when redressing the surface it should be done again. If not, a loss of tone can occur (sustain I wonder?).

I don't think many rebuilders heat temper the bearings but I have always wondered if it's something they *should* be addressing, and if some sustain problems in the treble might reverse themselves if the surfaces were heat tempered.

I am also interested to learn the exact technique of heat tempering. I know it has to do with torch heating the metal until a certain color is achieved.

I would be interested in anythng further you would add pertaining to the above thoughts.

Regards,

Rick Clark

Tempering means making the metal softer. The normal way to treat steel is to harden it, and then temper it to the desired softness. Hardening is accomplished by heating the metal very hot, and then cooling it suddenly. Tempering is heating the metal to a controlled temperature, and then letting it cool slowly. The traditional method of tempering involves polishing the metal, heating it until the color of the oxidation reaches a certain color, depending on how hard you want the metal to end up, and then letting it cool slowly.

My own two cents worth of wisdom: No matter how good a piano is in other ways, there is always a way of doing jobs like restringing that will result in a lousy job. This one truism is the largest single factor in how good an old piano will sound.